trap? A slight swell on the sea can cause severe movement on
a crane jib perched 30 m above sea level when lifting on to
unmanned platforms with no fixed crane. If you are working in
swampy areas, flat-bottom barges may be required to mobilise
the equipment.
The logistics involved in navigating a large slow moving
barge through a shallow waterway requires a degree of skill
and local knowledge. Later, you will also need to mobilise
the crew along with all other associated personnel to site,
which may take place one week after the barge departed.
Have you considered standby charges for the equipment
and technicians? The week long journey to the site has now
cost you seven days of equipment rental plus potentially 14
man days of technician time. Averaging those costs across
three different vendors on a recent inspection project I was
managing would place them at around £49 000 (US$75 000)
and that is prior to the pig even seeing the pig trap!
Power and shelter
Power
Will your chosen inspection company require an electricity
supply on site to power up laptops and electrical equipment
to commission the inspection tool? If so what voltage and
frequency is required, and is it available at the work site?
Shelter
What are the typical weather conditions for the region, wet,
cold, hot and humid? I have had the opportunity to work in
the extremes from 50˚C in the Saudi Arabian desert to -40˚C
in the Vasyugan swamp, the largest swamp in the northern
hemisphere and I have experienced issues with the sensitive
inspection tool electronics in both extremes.
How will you protect these tools to ensure they function
correctly when they arrive on site and are prepared for use? You
may have conducted your site survey in the summer and the
inspection may not happen until the winter, or indeed vice versa.
Have you taken the seasonal variations into consideration?
Personnel
Will they require Visa paperwork? Does your pipeline pass
through different countries? Will you have to prepare letters
of invitation for an embassy? Armed security may be required
if working in hostile environments. Transportation in remote
areas may require the use of a helicopter to deploy Above
Ground Markers for example.
)
)
Training – do you have specific training courses that
personnel are required to attend? Offshore survival,
off-road driving, altitude awareness, hydrogen sulphide
awareness, may be required, to name but a few.
)
)
Consideration must also be given to the health of
personnel – inoculations maybe required. Malarone or
similar malaria tablets may be necessary, or in one of the
strangest cases I’ve come across, I had to keep medication
with me in case of contracting Bubonic plague, as there
was an outbreak during the time I travelled to Kazakhstan
back in the early 2000s.
)
)
Food and shelter – is there a hotel close by or will
personnel be staying on a camp environment or at a
cramped offshore installation with eight people sharing a
room and a communal shower block?
Piggability report
The piggability report will collate all of the information
gathered from the site visit and the document review and
confirm if the pipeline is piggable, or not. If the pipeline is
not piggable recommendations will be made on modifications
required or alternative methods to be employed, e.g.
bi-directional inspection technologies, crawler pigs etc.
Potential threats for individual pipeline segments will be
investigated to ensure each inspection is tailor made. Does
the pipeline run through areas, which suffer from ground
movement? If so, an inspection tool fitted with an inertial
mapping unit may be recommended to measure bending
strain. The type of product the tool is running in needs to be
considered, you cannot run an ultrasonic tool in a gas pipeline
without a liquid couplant for example.
Depending on your requirements an independent review
of inspection vendors may be performed with budget prices
and availability of the inspection tools included.
Figure 3.
Offshore ILI loading.
Figure 4.
Pipeline debris.
FEBRUARY 2016
/
World Pipelines
93
